ADLINK Technology arm AMPERE COM-HPC-ALT - Miscellaneous Signals

COM-HPC-ALT User’s Guide PICMG COM-HPC R1.0
Page 28 Copyright © 2023 ADLINK Technology, Inc.
4.3.15 Miscellaneous Signals
Name
Pin #
Description
I/O
PU / PD
Comment
WD_OUT
B11
Output indicating that a watchdog time-out event
has occurred. Refer to Section 5.3 for details.
O 3.3V
WD_STROBE#
B10
Strobe input to watchdog timer. Periodic strobing
prevents the watchdog, if enabled, from timing out.
I 3.3V
PU 10K
FAN_PWMOUT
C11
Fan speed control for a secondary system fan. The
primary fan control signals for CPU thermal
management are on the Module, along with a vendor
specific connector.
Fan controls use the Pulse Width Modulation (PWM)
technique to control the fan’s RPM. CMOS output;
Carrier designers should buffer this signal with an
open drain FET and pullup or other robust Carrier
device(s).
O 3.3V
FAN_TACHIN
C12
Fan tachometer input for a fan with a two pulse
output for the secondary fan.
I OD
3.3V
PU 1K
RSVD
Reserved pins. These may be assigned functions in
future versions of this specification. Reserved pins
shall not be connected to anything, and shall not be
connected to each other.
WD_OUT
If a Module supports a watchdog timer it shall minimally support output mode 1 and may also support output modes 2 or 3 as defined in the table
below. The selection of the output modes may be realized by software configurable hardware or by Module build options.
WD Mode
Description
Comment
1
The Module generates an internal reset. Module output pin PLTRST# is driven low. The WD_OUT
pin is driven high until the unit resets.